Envelop



(No Mo deL) I. A. CE'NTERVALL.

ENVELOP.

No. 580,871. Patented Apr. 13, 1897.

WITNESSES S INVENTOIQ 5 ,9 flax/MK m 5 .Attorney IVAN A. CENTERVALL, OF BOSTON, MASSACHUSETTS.

ENVELO P.

SPECIFICATION forming part of Letters Patent No. 580,371, dated April 13, 1897. Application filed November 27, 1896. Serial No. 613 ,549. (N0 model.)

To all whom it may concern:

Be it known that I, IVAN A. CENTERVALL, a subject of the King of Sweden and Norway, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Envelops; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to envelops, and has for its object to provide a simple, cheap, and efficient safety-envelop from which the contents cannot be removed without so mutilating the envelop as to make it apparent that such removal has been attempted.

To this end the invention consists in an improved safety envelop embodying certain novel features and details of construction, as hereinafter particularly set forth, illustrated in the drawings, and pointed out in the claims.

In the accompanying drawings, Figure lis a plan view of the paper blank from which the envelop is formed. Fig. 2 is a plan view showing the envelop partially folded. Fig. 3 is a similar view showing the envelop folded except the sealing-flap. Fig. 4 shows the envelop ready for mailing.

Similar numerals designate corresponding parts in the several figures of the drawings.

The improved envelop is formed in one piece from a single blank and comprises a rectangular main body portion 1, having connected to one of its longitudinal edges an inner side flap 2 and to its opposite edge an outer side flap 3.

At one end of the body portion 1 is arranged a longitudinal narrow flap 4 and at the opposite end is the terminal or closing flap 5, having a longitudinally-extending tab 6. The first flap to be folded is the narrow longitudinal one 4, and this is provided near its junction with the body portion 1 with a widened base 7, to which the gummed edge of the outer side flap 3 is adapted to adhere. After the flap 4 has been folded upon the body portion 1 the inner side fiap 2 is folded upon the body portion and upon the flap 4, as shown in Fig. 3. The flap 2 is slightly less in width and length than the outer side flap 3, said flap 2 being cut away, as indicated at 8, so that when the flap 3 is folded upon the flap 2 the gummed edge 9 of the flap 3 will stick to the base portion 7 of the fiap 4. The outer side flap 3 is next folded inward upon the flap 2, and being gummed upon its longitudinal as well as its end edges it adheres to the flap 2 near its fold and also to the outer ends of the flap 2, adjacent to the mouth of the envelop.

The flap 2 is provided near the mouth of the envelop with a notch 10, and when the flap 2 is folded upon the narrow flap 4 the extremity of the latter is exposed beneath said notch 10. Now when the flap 3 is folded its gummed edge comes in contact with the extremity of the narrow flap 4 under the notch 10 and said flap 4 is thus firmly secured in place. Alining apertures 11 are provided in the flaps 2 and 3, through which the tab 6 is adapted to be inserted, as illustrated in Fig. 5.

The edge of the terminal or sealing flap 5, as well as the Whole inner surface of the tab 6, is gummed, so that when said gummed portions have been moistened and the tab 6 inserted through the apertures 11 the tab 6 adheres to the longitudinal narrow flap 4 and the sealing-flap 5 adheres to the outer surface of the outer side flap 8, thus securely sealing the envelop and preventing the possibility of the removal of the contents thereof without detection. .The stamp (indicated at 12) is preferably applied in such manner as to lap partially over the sealing-flap 5, thus affording additional protection. By causing the outer side flap 3 to adhere to the narrow flap 4 it will be impossible for aletter-sheet to be slipped in between the side flaps 2 and 3.

The envelop above described is extremely cheap and economical in manufacture, and

also possesses the important advantage of being safe and reliable.

It will be apparent that various changes in the form, proportion, and minor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

Having thus described the invention, what I claim is- 1. A safety-envelop comprising a body portion, a narrow longitudinal end flap, opposing side flaps adapted to be folded thereon and sealed, and also provided with registering apertures, and a closing-flap having alongitudinally-extending tab which is gummed and adapted to be inserted through the apertures and side flaps and to adhere to the narrow longitudinal flap near its extremity, substantially as described.

2. Asafety-envelop comprising a rectangular body portion, a narrow longitudinally-extending end flap, an inner side flap notched at one end as described, an outer side flap having its edges gummed and adapted to adhere to the inner side flap and to the extremity of said narrow flap at its end, said side flaps being provided with registering apertures, and a terminal or closing flap having a gummed tab adapted to be inserted through the apertures and to adhere to said narrow flap, substantially as described.

3. A safety-envelop comprising a rectangular body portion, a longitudinally-extending end flap folded thereon, cut away at its opposite ends to expose portions of said longitudinal end flap, an outer side flap gummed at its edges and adapted to adhere to the inner side flap and to the exposed portions of the longitudinal flap, and a terminal portion or sealing-flap provided with a gummed tab or extension adapted to be inserted through registering apertures in said side flaps and to adhere to said longitudinal end flap, substantially as described.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

IVAN A. OENTERVALL.

WVitnesses:

CHARLES E. TRAUT, G. E. STRATTON.

an inner side flap 

